A fanfiction could revolve around a mission. Naruto is away on a long - term mission, and Himawari, who idolizes Female Sasuke, gets the chance to go on a small local mission with her. Female Sasuke teaches Himawari some unique ninja skills. When Naruto returns, he is surprised at how much his daughter has grown under Female Sasuke's tutelage, and this also brings the three closer together in an unexpected way.
One idea could be a story where Boruto and Himawari discover an old diary of Naruto's from his early days as a ninja. Hinata helps them understand the context and the values their father held. They then use those lessons to face a new threat in the village.
One idea could be a story where Boruto and Himawari discover an old lemon tree in the Hidden Leaf Village. Naruto and Hinata then tell them about a legend that the tree was planted by the first Hokage. The kids decide to take care of the tree and throughout the process, they learn more about their family's history and the importance of nature in their village.
One idea could be a story where Naruto and Sasuke have to team up with Karin to face a new, powerful enemy. Maybe they initially don't trust Karin completely, but as they go through battles together, they start to respect her abilities more and form a strong bond as a team.
A fanfiction could be about Sai trying to befriend Sasuke. Sai, who is often socially awkward, attempts to break through Sasuke's cold exterior. Meanwhile, Naruto is caught in the middle, trying to help Sai while also dealing with his own complex relationship with Sasuke. It could be a story full of humor and some tense moments.
One idea could be a story about their team training. Naruto's enthusiasm, Sasuke's intensity and Sai's unique combat style could lead to interesting training scenarios. They could learn from each other's strengths and overcome their weaknesses together.
Think about a prophecy or a hidden power. Suppose there is a prophecy that says only the union of Uzumaki, Hyuga and Uchiha blood (represented by Naruto, Himawari and Female Sasuke respectively) can unlock a great power. This power is needed to save the ninja world from a coming darkness. The story can be about their journey to discover and master this power, with all the personal and external conflicts that come with it, like distrust from other ninja clans or internal struggles within the group.
A fanfiction where they all go on a mission together in a strange, uncharted land. Kakashi is the leader as usual. Sasuke could struggle with his inner demons during the mission, Naruto would be trying to keep everyone's spirits up, and Sakura would be using her medical skills to keep them all in top shape. There could be new enemies and challenges that they have to face together, forcing them to rely on each other more than ever.
One idea could be a story where Sasuke, with his Sharingan, discovers a new power related to the Rinnegan that was hidden within Naruto all along. Maybe Naruto has some dormant Sage of Six Paths energy that when combined with Sasuke's powers, they can unlock a new level of strength to fight a powerful, unknown enemy.
In a fanfiction, they could be in a different world altogether. Maybe they are in a modern - day city. Naruto is still the energetic one, trying to make friends everywhere. Kiba has Akamaru as his service dog. Sasuke is the brooding loner who is actually a really good artist. Shino is the quiet one who is into entomology and often shares interesting facts about bugs with the others.
One idea could be a story where Sasuke and Naruto have to team up again for a dangerous mission, and Hinata and Sakura also join in. During the mission, Hinata might use her Byakugan to detect hidden enemies, while Sakura uses her medical and combat skills to support the team. And Sasuke and Naruto could have some deep conversations about their past and future, like they did in the original series.